I am a faculty member in the Department of Computer Science and the Cognitive Science Program at the University of Toronto, where I direct the Cognitive Lexicon Laboratory. My research explores the cognitive and computational foundations of the human lexicon.
Natural language uses a finite vocabulary to express an unbounded array of ideas. I investigate how language users adapt their lexicon to communicate emerging meanings across long timescales (such as historical language evolution) and short timescales (such as child language development), and what shared cognitive principles and mechanisms govern these processes. Recent themes of my research include modeling semantic change and lexical innovation, crosslinguistic analysis and the computational study of how language intersects with other domains such as morality.
Evolution and development of the lexicon
- Li, J., Armstrong, B.C., and Xu, Y. (2026) Discovering regularity and mechanisms of word sense acquisition in childhood. PNAS, 123(20), e2525788123.
- Yu, L. and Xu, Y. (2025) Infinite mixture chaining: An efficiency-based framework for the dynamic construction of word meaning. Open Mind, 9, 1-24.
- Xu, A., Kemp, C., Frermann, L., and Xu, Y. (2024) Word reuse and combination support efficient communication of emerging concepts. PNAS, 121(46), e2406971121.
- Brochhagen, T., Boleda, G., Gualdoni, E., and Xu, Y. (2023) From language development to language evolution: A unified view of human lexical creativity. Science, 381(6656), 431-436.
- Sun, Z., Zemel, R., and Xu, Y. (2021) A computational framework for slang generation. TACL, 9, 462-478.
- Xu, A., Stellar, J.E., and Xu, Y. (2021) Evolution of emotion semantics. Cognition, 217, 104875.
- Ferreira Pinto Jr., R. and Xu, Y. (2021) A computational theory of child overextension. Cognition, 206, 104472.
- Habibi, A.A., Kemp, C., and Xu, Y. (2020) Chaining and the growth of linguistic categories. Cognition, 202, 104323.
- Ramiro, C., Srinivasan, M., Malt, B.C., and Xu, Y. (2018) Algorithms in the historical emergence of word senses. PNAS, 115(10), 2323-2328.
- Xu, Y., Malt, B.C. and Srinivasan, M. (2017) Evolution of word meanings through metaphorical mapping: Systematicity over the past millennium. Cognitive Psychology, 96, 41-53.
- Xu, Y., Regier, T. and Malt, B.C. (2016) Historical semantic chaining and efficient communication: The case of container names. Cognitive Science, 40(8):2081-2094.
Analysis of crosslinguistic structures
- Fugikawa, O., Hayman, O., Liu, R., Yu, L., Brochhagen, T., and Xu, Y. (2023) A computational analysis of crosslinguistic regularity in semantic change. Frontiers in Communication, 8:1136338.
- Hahn, M. and Xu, Y. (2022) Crosslinguistic word order variation reflects evolutionary pressures of dependency and information locality. PNAS, 119(24), e2122604119.
- Xu, Y., Duong, K., Malt, B.C., Jiang, S., and Srinivasan, M. (2020) Conceptual relations predict colexification across languages. Cognition, 201, 104280.
- Xu, Y., Liu, E., and Regier, T. (2020) Numeral systems across languages support efficient communication: From approximate numerosity to recursion. Open Mind, 4, 57-70.
- Kemp, C., Xu, Y., and Regier, T. (2018) Semantic typology and efficient communication. Annual Review of Linguistics, 4:109-128.
- Ramezani, A., Stellar, J.E., Feinberg, M., and Xu, Y. (2026) Historical reconstruction of human moralization with word association and text corpora. Nature Communications, 17, 3412.
- Ramezani, A. and Xu, Y. (2025) Moral association graph: A cognitive model for automated moral inference. Topics in Cognitive Science, 17, 120-138.
- Ramezani, A. and Xu, Y. (2023) Knowledge of cultural moral norms in large language models. In ACL.
- Prystawski, B., Grant, E., Nematzadeh, A., Lee, S.W.S., Stevenson, S., and Xu, Y. (2022) The emergence of gender associations in child language development. Cognitive Science, 46, e13146.
- Xie, J.Y., Ferreira Pinto Jr., R., Hirst, G., and Xu, Y. (2019) Text-based inference of moral sentiment change. In EMNLP-IJCNLP.
